It is estimated that 2 million healthcare infections occur each year in the United States alone, causing 90,000 deaths. Treatment of these infections is estimated by the CDC to cost $5 billion per year. Usually, antibody and other chemical detection methods have made it possible to identify several thousand bacteria species. However, accurate as these methods are, they tend to suffer from the long periods of time required for identification. Long-time bacteria detection and characterization times may compromise the effectiveness of chemotherapy and can allow the infection to increase. Further, the long-time detection may allow the bacteria to develop immunity.
Several methods have been proposed for the identification of bacteria strains, these include differences in the spectra of viable bacteria, fluorescence and IR spectroscopy, and chemiluminescence. Fluorescence spectroscopy has identified Escherichia coli and Staphylococcus aereus, and some 25 strains have been also identified by their fluorescence spectra excited at 250 nm. Auto-fluorescence has also been employed for the rapid detection and classification of bacteria. Similarly, bacteria rapid identification has been reported using principal component analysis. In addition, the identification of bacteria in culture plates and liquids has been reported. These methods have been successful in the identification of many viable bacteria strains in various media, which not only minimizes the period of time required for identification and classification of bacteria, but also provides an easy and rather inexpensive means for the identification of bacteria.